Printing plate anchorage



' Y 1941? G. E. BOMBERGER ETAL 2,249,938

PRINTING PLATE ANCHORAGE Filed Feb. 23, 1940 Patented July 22, 1941PRINTING ILATE ANCHOR/AGE George E.'Bomberger and Howard H. Niederauer,Indianapolis, Ind., assignors to Inland Container Corporation,Indianapolis, Ind., a corporation Application February 23, 1940, SerialNo. 320,356 4 Claims. (01. 101-4151) This invention relates to thecylinder printing of corrugated, solid fibre, or like materialcontainers.

In the printing of such material the runs may be large or small.However, the preparation of printing surface and its application to theprinting press requires a fixed amount of time, regardless of thequantity of the orders. The container manufacturers are faced with aservice problem which requires quick delivery of containers, and becauseof' the quick service the Because of the high cost of printing presses,or more particularly, combination printers and slotters, it is desirablethat all possible preparatory work on a new printing surface sheet bedone prior to the shut down of the press for the printing surfacedemounting and mounting This invention covers the bonding operations. ofthe printing dies to the printing surface sheet in the spaced relationnecessary to meet the requirements of the container or board blank to beprinted by each cylinder.

of the printing surface sheet and of a size suitable for engagement inthe receptacles or anchorages provided in the printing cylinders.

The present practice in applying printing Strips of suitable materialare then combined to two parallel edges ,20 This invention plates to thecylinders is to use one of the fol- L lowing processes.

1. In the case of wood cylinders, to place tacks through the printingsurface sheets and the printing dies to the extent that both theprinting surface sheet and printing die will conform to the curvature ofthe cylinder.

2. In the case of metal cylinders, the printing die is usually mountedon a curved metal backing which is locked with lugs to the cylinder.

3. In some cases the printing dies are bonded I to curved, punched,metal plates which can be tacked on to Wood cylinders. v

The chief feature of the invention is the accomplishment of said objectsby utilizing a printing surface sheet which is flexible for supportconformation and to which is secured by adhesion or the like, theimpression forming means, the flexible printing surface sheet beingrelatively inextensible, and the mounting of such a printing surfacesheet in adjusted and tautened relation upon said support, usually arigid cylinder of metal or other suitable material, such as wood.

For simplicity, the invention is disclosed as applied to a singleimpression embodiment of the invention and one wherein the invention isarranged to simultaneously print a number of containers of the same sizeor dissimilar sizes, and for the same or different purchasers.

The full nature of the invention will be understood from theaccompanying drawing and the following description and claims:

In the drawing,

Fig. 1 is a perspective view of a printing plate embodying theinvention.

Fig. 2 is an enlarged sectional view of one form of enlarged endanchorage upon such a plate.

Fig. 3 is a side elevation of one form of printing cylinder embodied inthe invention.

Fig. 4 is an enlarged sectional View of two adjacent dissimilaranchorages for plate anchorage.

Fig. 5 is a side elevation of one form of plate tension retaining lock.

Fig. 6 is a developed plan of a printing cylinder with a plurality ofprinting plates of the same and dissimilar size thereon. 1

It is the purpose of this invention to provide a quick printing surfaceon the printing press which will result in a considerable decrease inthe amount of down time required for a printing surface sheet change onthe printing machine. The printing surface sheet would carry the centerline in both directions and when properly positioned on the cylinder, inrelation to the center lines of the cylinder, the enlarged end 14, Fig.1, would be inserted in the opening ll, Fig. 3, and then wrapped aroundthe cylinder, placing the remaining end section M,

in the recess 23, and the cylinder 2|. would.

then be rotated clockwise, locked in position and in a tauteningposition, with the ratchet 25 and mounted on separate printinlg surfacesheets and it is only necessary, in this case, after the completion ofone job, to loosen the sheet or sheets, move it or them to the properposition for the next job, lock it or them up and start production.

The standard printing machines for container manufacture are designed topermit quick adjustment of the timing of two or more cylinders and,therefore, it is only necessary to shift the printing dies on thecylinder in the end-to-end direction to meet the requirements-ofdifferent size containers or blanks to be printed, that require only achange in the spacing of the blanks in the end-to-end direction of theprinting cylinder.

The principal advantages of this invention are the reduction in downtime of costly presses, accurate positioning of dies and an increase inthe life of the dies because of the elimination of tacking when woodcylinders are used, or clamping or screwing in the case of metal facedcylinders.

For a better understanding of the invention, the present practices arebriefly reviewed as follows: 7

The first operation in the manufacture of corrugated or solid fibrecontainers, in the case of corrugated containers is that of corrugatingthe center member and then applying the liners. And, in the case ofsolid fibre board is that of laminating plies of paperboard to developthe proper caliper. This operation sometimes includes the slitting ofthe mill run widths to the desired container'blank widths and theaddition of the scores which run in that direction.

This first operation is one that generally permits rather uniformproduction in lineal feet per hour, regardless of the number of ordersincluded in an hours run. However, when We get down to the finalblanking and printing operation, the machine preparation or setup isquite a variable factor. In the corrugated industry, costly printingpresses or combination printers andfslotters are out of operation from40% to 60% setups on these machines. It is, therefore, veryimportantthat ways and means be developed to reduce the down time onprinters or printing and slotting equipment, so as to level out the flowof production throughout the container plant.

A relatively large percent of the rubber dies or stamps inherently warpand it is extremely difiicult, unless the same are individually mountedwith extreme care, to insure that unifornr and perfect work is obtainedfrom the die which has warped.

The present invention contemplates the use of rubber dies or stampswhich, whether warped or not, can be properly mounted upon a flexible,inextensible sheet arrangement so that when the flexible, inextensiblearrangement is mounted upon the supporting printing cylinder, theaforesaid warpage of the die or stamp is eliminated.

In Fig. 1 of the drawing, It indicates a sheet of kraft paper, which isrelatively nonexpansible although it is very flexible. A length ofkraftpaper for a sheet developed for practically wrapping the entire face ofa 15-inch diameter cylinder or the like is relatively inextensible.

To this sheet III, there is adhesively secured the several rubber diesor stamps II. As previously stated, these rubber dies or stamps aresubject to buckling or warping but it is quite obvious that they may beaccurately positioned on the sheet and adhesively secured thereto as atI2, see Fig. 2, and held under pressure, letter press fashion, in thepredetermined position on said make-ready sheet until the entireadjacent faces of the sheet and die or stamp are adhesively securedtogether with the die in flattened relation. This eliminates the warpingin the die or stamp but only temporarily. Immediately upon release ofthe pressure, the warping efiect returns to the die or stamp, and thedie or stamp and that mounting portion of the sheet warps accordingly.Each end of the sheet In is enlarged as shown clearly in Fig. 1.

In Fig. 2, one method of sheet end enlargement is illustrated. Herein,there is secured an anchor strip I3 and the kraft paper I0, as indicatedat I4, is wrapped therearound one or more times. Each of the two ends ofthe sheet II] is thus formed with enlargements in this or any otherequivalent character. The strip I3 may comprise a wood member or may bea member of solid fibre stock and if of the latter character, may beformed from trimmings obtained as a result of the formation of solidfibre containers to which this invention also is readily applicable forthe printing thereof. It is to be understood that the ends are so formedthat they are truly parallel insofar as it ispossible to make themparallel.

Reference now will be had to Fig. 3. In said figure, the numeral I5indicates conventionally a shaft which supports a printing drum orcylinder I6, the method of support being not illustrated. The peripheralsurface of this cylinder is wood and is relatively rigid. Formed thereinthere is a recess I1, the detail arrangement of which is shown mostclearly in Fig. 4. This recess is of suflicient depth to provide anoverhanging tongue portion IB and the portion of the recess below thetongue is at least equal to the width of the enlarged end I4 and thewidth of the throat I9 of said recess adjacent the tongue is at leastequal to the thickness of the end I4 so that one enlarged end of theprinting surface sheet, previously described, may be radially seated insaid recess I! and the relatively inextensible but flexible sheetwrapped around the cylinder I6 until the other end is positionedadjacent the anchored end. When longitudinal or end seating, asdistinguished from radial or surface seating, is employed, the throat I9need only be large enough to pass the thickness of said sheet.

As hereinafter pointed out, the sheet need not wrap entirely around thecylinder. Also, as hereinafter described, recess II utilized need not bepositioned adjacent the adjustable anchorage hereinafter moreparticularly described.

The container industry has standardized on very few diameters ofprinting cylinders and the majority of container plants do not have morethan two diameter cylinders to deal with. Therefore, it is a very simplematter to position the locking recesses I! and 23, so that a printingsurface sheet made up to fit a small cylinder Adjacent the anchoringrecess, there is provided in the cylinder a tangential cylindrical boreand mounted and rotatable therein is a similar cylinder 2|. The cylinder3 has a throat 22 communicating with the bore and the width of thisthroat is appreciably greater than the width of the other end M of theprinting surface sheet. for radial seating. The tautening cylinder 2|includes a recess 23, preferably rectangular in form as shown, the depththereof being at least equal to the thickness of the anchoring end I4and the width thereof being at least equal to the width of the anchoringend I4.

The free end I l, previously mentioned, of the printing cylinderencircling printing surface sheet, then is seated in the recess 23 whenthe latter registers with the throat 22. Following such seating, theprinting surface sheet will bag about the cylinder IS. The cylinder 2|then is rotated clockwise-see Fig. 4-and this slack or bag is taken upand as it is taken up, the recess seated end I4 is carried by saidrecess 23 clockwise and the body portion ID of the make-ready sheetimmediately adjacent that end passes between the inner wall of the bore20 and the outer surface of the cylinder 2|. The end I4 is also includedwithin bore 20.

This rotation is effected by means of a detachable handcrank, not shown,associated with either squared end extension 24 of a shaft which mountsthe cylinder 2| in cylinder I6. Referring to Fig. 5, it will be notedthat one extension of the aforesaid tautening arrangement mounts aratchet 25 and associated therewith is a locking pawl or dog 26pivotally supported at 2'! onthe adjacent end of the cylinder I6. Thecylinder 2| may be nested in cylinder IS, the bore 20 having a shaftreceiving closure.

A spring 28 anchored as at 29 upon the cylinder |G normally constrainsthe pawl into ratchet engagement. Thus, when the cylinder 2| is rotatedclockwise-see Fig. 4-the ratchet 25 freely passes or moves relative tothe pawl but ratchet return movement is preventedby reason of theratchet and pawl locking arrangement, The force of this spring 28 issuch that centrifugal force upon the pawl is insufficient to disengagethe pawl from looking arrangement with the ratchet. However, the pawlmay be disengaged from the ratchet by manually moving said pawltherefrom when the ratchet has been advanced an amount in the tauteningdirection sufficient to permit the end of the pawl to clear the adjacentratchet tooth for printing surface sheet release from the supportingcylinder.

It will be obvious that the printing surface sheet can be veryexpeditiously prepared and of materials of relatively low cost and whichwill have a length of life quite suflicient for the commercial purposeto which the invention is applied, since there is but little wear on thesheet other than on the dies incident to the printing operation.

In the tautening action of this flexible, relatively inextensibleprinting surface sheet, it will be quite clear that initially theaforesaid sag or slack will be taken up and then the paper printingsurface sheet arrangement will be caused to engage intimately throughoutits area the adjacent supporting area of the cylinder Hi. In thisaction, the warping of the dies, previously mentioned, which warping iscarried through to the paper, is eliminated so that the dies when theprinting surface sheet structure is mounted in tautened relation on thecylinder, function as if there were no warping in said dies or sheet.

For extending the range of accommodation of the invention and toeliminate the necessity of having all of the printing surface sheetstructures of like length, the cylinder |6 may have included thereinother anchoring slots suitably spaced apart. Thus, the work, which is ona very small printed area or form, would be printed by a printingsurface sheet that would have its nonadjustable, anchored end seated inthe slot closest to the adjustable anchorage and offset therefrom in acounter-clockwise direction and other printing surface sheets of greaterlength but less than the full length equal to cylinder peripherallength, would be seated in intermediate slots ll, of which two areillustrated by way of example, in similar direction.

As shown clearly in Fig. 6, it is quite clear that when the printingplate structures are made to have predetermined lengths, and since theyare substantially inextensible, that printing of large and small sizeboxes may be effected at the same time, it being understood that onerotation of the printing roll secures one impression. In Fig. 6 there isa developed length representation of two printing surface sheets of thesame length and a printing surface sheet of a shorter length. All,however, are tautened and tensioned simultaneously by the same tauteningand tensioning device.

It will be obvious that the structure disclosed is capable of printing acontainer blank the full width of the cylinder or of a lesser width andthat the printing surface sheet may be adjusted longitudinally of theaxis of the printing cylinder.

The gist of the invention, it will be apparent, resides in the fact thatthe mounting portion I0 of the printing surface sheet structure issubstantially inextensible and since this can be of kraft paper, theinvestment in printing surface sheet structures is infinitesimal if therubber die portions be excluded.

Furthermore, after many runs, the printing surface sheet structure mayrequire renewal, which is effected by merely removing the dies II andreplacing the same on a new mounting portion |0-|3-|4. These printingsurface sheets |U|3|4 without dies may be fabricated and held in stock,the lengths thereof being those corresponding to the arcuate distancesbetween the tautening arrangement and the several anchoring slots.

It will also be obvious that the make-ready period cost can bematerially reduced because the make-ready operator can prepare otherprinting surface sheet structures by mounting dies thereon while otherruns are being made and upon completion of such runs, the newlyfabricated printing surface sheet structure, or structures, can besubstituted in short order for those previously employed.

It is to be understood that the details of construction shown in Figs. 2to 5, inclusive, and the exemplification of a multiple embodiment of thebasic invention shown in Fig. 6 is given by way of example only.

It is to be understood, also, that certain major portions of theprinting copy often are common to various items of a customerscontainers, the principal differences being in minor plate changes orchanges covering contents, model numbers and the like.

When the supporting cylinder is of wood, after the make-ready sheet hasbeen applied, the brand stamnmay be tacked to the cylinder through themake-ready.. sheet. Upon completion of that brand order, the brand stampor 'die may be quickly removed from cylinderand printing surface sheet,and another brand stamp applied. in like manner, and thesecond brandcontainers run.

A full line of brand containers of like size can thusbe run witha-minimum of down time. Thereafter, for another size of container, ifthe printing dies.- and printing surface sheets are laid'out properly,the. same may be properly spaced apart by shifting the sheets closertogether or farther apart or shifting the dies and the several brandruns repeated without requiring removal of the printing surface sheetsfrom the roll, provided that the brand dies have not been tacked to thecylinder. If tacked, these dies must be removed and retacked when thesheets are readjusted.

. By referring to Fig. 3; it will be noted that adjacent cylinder [6 ispressure cylinder B, and therebetween is the gap A. Cylinder B isadjustable toward and away from cylinder l6 in accordance with stockutilized for container formation. Both cylinders, however, have the samerelative peripheral speeds.

Now, if the customers plates, dies or stamps are worn down, or initiallyare not of the usual height or. thickness, the plate is shimmed orpadded out from the cylinder by spacing means such asthick and/or thinsheets as required so thatthe peripheral speeds of the pressure rollface and printing face of ,the' stamps, dies or plates are the same.

It is also to be understood that the printing roll can be adjustedangularly about its axis relative to the pressure roll. In this manner,the position of the printing stamps can be advanced or retracted so thatthe impression on the container blank can be properly located. Thisfeature of adjustment, however, is common to printer-slotters but ismentioned since containers having but one variable dimension andrequiring the same printing dies can be printed in successive runs bymerely angularly regulating or adjusting the position of the aforesaiddies, stamps or printing plates.

A brief summary of some of the advantages of this invention, includingsome mentioned hereinbefore, are as follows: 7

' A. Continuity of flow of product;

B. Reduction in the wear and tear on printing plates;

C. Ability to use warped or buckled plates;

D. Definite reduction'in the time required for removing the printingplates from the cylinders;

E. Simple mechanical means for locking and tautening make-readysheetahaving few moving parts and elimination of delicate parts whichwould easily become clogged with ink;

F. Locking and tautening means uses minimum area of'the cylinder;

G. In the case of wooden cylinders, we definitely reduce the wear andmutilation of the cylinders because of the elimination of the majorityof the tacks required inthe old process. This results in maintaining amore nearly perfect cylinder face which is necessary for high gradecertain minor plates at the end of one run and tacking substitute platesinto position for the next job;

I. This type of printing surface sheet can be attached to the cylinderand removed from the cylinder many times without any apparentdepreciation or damage to the printing surface sheet. In the formermethod, the tacking through the printing surface sheet causedconsiderable damage to it, particularly at the top and bottom edges and,consequently, shortened its life; 7

J; This method permits quick and accurate positioning on the cylinder,which isparticularly advantageous on close register work;

K. This printing surface sheet permits the calipering of the printingplates and the use of shims, or padding, under the lower plate on themake-up table and eliminates this costly item of down-time on theprinting press.

L. This make-ready method permits mounting two or more printing surfacesheets on the same cylinder for jobs requiring practically the same dieswith only a change of positioning or a change in centers in theend-to-end direction of the cylinder.

While the invention has been illustrated and described in great detailin the drawing and foregoing description, the same is to be consideredas illustrative and not restrictive.

The several modifications described herein, as well as others which willreadily suggest themselves to persons skilled in this art, all areconsidered to be within the broad scope of the invention, referencebeing had to the appended claims.

The invention claimed is:

1. A tautening and adjustable anchorage for relatively inextensibleflexible printing surface sheets including an elongated cylindrical borein a printing cylinder and parallel to the axis thereof and adjacent thecylinder periphery and having a throat of appreciable arcuate widthcoincident with the projected continuation of the periphery, anelongated cylindrical support member rotatably mounted in said bore andincluding an elongated recess in the support surface and parallel to theaxis of the support, a relatively inextensible, flexible printing sheethaving an enlarged end freely and radially seatable in said recess whenthe latter registers with the throat, said bore receivable member uponrotation in the bore simultaneously locking the printing surface sheetenlarged end in the recess by bore wall cooperation and tautening thesheet on the cylinder, and means associated with the bore' receivablelongitudinally recessed member for normally holding the same in rotatedrelation with the recess ofi'set anguluarly from the throat for recessclosure and for printing surface sheet anchorage retention tautening. v2. A tautening and adjustable anchorage for relatively inextensibleflexible printing surface sheets including an elongated cylindrical borein a printing cylinder and parallel to the axis-thereof and adjacent thecylinder periphery and having athroat of appreciable arcuate widthcoincident with the projected continuation of the periphery, anelongated cylindrical support member rotatably mounted in said bore andincluding an elongated recess in the support surface and parallel to'theaxis of the support, a relatively inextensible, flexible printing sheethaving an enlarged end freely and radially seatable in said recess-whenthe latter registers with the throat, saidbore receivable member uponrotation in the and printing surface sheet bore simultaneously lockingthe printing surface sheet enlarged end in the recess by bore wallcooperation and tautening the sheet on the cylinder, means associatedwith the bore receivable longitudinally recessed member for normallyholding the same in rotated relation with the recess offset angularlyfrom the throat for recess closure and for printing surface sheetanchorage retention and printing surface sheet tautening, the printingsurface sheet having an opposite end similarly enlarged, the cylindnerhaving a longitudinally directed surface groove therein peripherallyspaced from the throat slightly less than the length of the sheetbetween enlarged ends, the groove having a throat at the cylinderperiphery through which the opposite end enlargement of the sheet isreadily passable, and a projection extending into the second-mentionedthroat adjacent the cylinder periphery and arranged for sheet oppositeend enlargement retention for tautening and positioning of the sheetupon the cylinder.

3. A combination as defined by claim 2, characterized by the cylindersurface including a plurality of identical grooves, the projectionstherein being similarly directed, one of the grooves being positionedimmediately adjacent the bore.

4. A combination as defined by claim 3, characterized by the width ofthe recess exceeding its depth and the depth of the groove exceeding itswidth, the sheets enlarged ends being rectangular in cross-section, therecess receivable end being flatwise receivable and the groovereceivable end being edgewise receivable.

GEORGE E. BOMBERGER. HOWARD H. NIEDERAUER.

